Open IQM File

The IQM file extension is associated with the Inter-Quake Model format, hence its initials.

The IQM format is a skeletal animation binary format designed for extensibility, efficiency, and ease of loading in both the animation engine and the game itself.

It is developed for Quake game engines and the like.

To open, create and modify an IQM model, it is necessary to have:

Inter-Quake Model Format Development Kit

Which, at this moment is maintained by a GitHub community